1. Field of the Invention
The present invention relates to an insertion device, a rotating tubular member, and a driving unit. The insertion device includes an insertion section extended along a longitudinal axis, and the rotating tubular member which is rotatable relative to the insertion section in directions around the longitudinal axis. The rotating tubular member is provided to (in) the insertion device. The driving unit is configured to transmit a rotation driving force to rotate the rotating tubular member.
2. Description of the Related Art
In an insertion device disclosed by way of example in the specification of U.S. Patent Application Publication No. 2012/002981, a rotating tubular member rotatable relative to an insertion section in directions around a longitudinal axis is attached to the insertion section extended along the longitudinal axis. In this insertion device, the rotating tubular member is attached to a base portion of the insertion section. A member channel is extended through an inside of the insertion section up to the base portion toward a distal direction. The member channel is open to an outside of the insertion section in an opening of an outer peripheral portion of the base portion. A driving unit is extended through the member channel with a driving axis being an axial center. The driving unit includes a driving shaft, which is a linear member, extended along the driving axis, and a gear portion provided to the distal direction side of the driving shaft. The driving unit is driven and thereby rotates in one of directions around the driving axis. The rotating tubular member is provided with an inner peripheral gear portion which is a driving force receiving portion. The inner peripheral gear portion is toothed with a gear portion in the opening of the member channel. The driving unit is driven, and the gear portion rotates in one of the directions around the driving axis, so that the rotating tubular member rotates relative to the insertion portion in one of the directions around the longitudinal axis.
The driving unit includes a supported portion provided to the distal direction side of the gear portion. A support portion which supports the supported portion is provided to the base portion. The support portion supports the supported portion so that the driving unit is rotatable in the directions around the driving axis.